Research needs in geology and hydrology . This discussion is limited to 

 geology as it is related to ecology; thus, gaps in the knowledge of the origin 

 of bedrock units are not discussed. Data gaps in bedrock, surficial deposits, 

 soils, marine and riverine sedimentation, and hydrology are assessed below: 



1. Bedrock: The distribution of bedrock types within the characterization 

 area has been well defined with the possible exception of the composition of 

 the bedrock underlying the outer islands. Little is known about the submerged 

 bedrock platform extending to the seaward limits of the characterization area. 

 Of particular interest concerning the latter fact is the potential for 

 commercial mineral mining in the shallow subtidal areas. The mineral 

 potential of terrestrial bedrock is fairly well known. 



The trace element content of plutonic rocks has been given much attention in 

 recent years, especially the radiogenic elements and the faults and fractures 

 (planes of separation and previous movement) that cut through consolidated 

 bedrock. The interest in the former centers around the amounts of radiogenic 

 material (available as uranium) and geothermal energy for power generation 

 and the amount of radon in the atmosphere. Radon in its gaseous form may be a 

 carcinogenic contaminant of groundwater supplies. Federally sponsored 

 research is now being undertaken to fill gaps in the data available on these 

 radiogenic elements, and some State and Federal research is being conducted to 

 answer questions on past fault movement during earthquakes and on the 

 influence of bedrock fractures on groundwater flow. More work, however, is 

 needed to meet knowledge needs in relation to seismicity and groundwater flow 

 through fractured bedrock. 



2. Surficial deposits: Knowledge of the distribution of surficial deposits 

 is adequate. Knowledge of the three-dimensional nature of these deposits is 

 lacking, however. It is known that much of the coastal area consists of 

 glacially derived sands and gravels under marine clay deposits, but the 

 distribution, thickness, and lateral extent of these coarser deposits are 

 largely unknown, except where specific engineering evaluations have been 

 conducted. 



Knowledge of these deposits is necessary in solid waste disposal, aquifer 

 identification and protection, evaluation of pesticide contamination of 

 surface and groundwaters, and location of future sand and gravel resources. 



The extent and volume of peat resources have become significant because of the 

 energy potential of peat. The resource volume in coastal Hancock and 

 Washington Counties is known, but Waldo County has many bogs that have not 

 been investigated as yet. Much also remains to be learned of the growth rate 

 of peat and the hydrology of peat bogs. 



3. Soils: Although the distribution of soils in the characterization area 

 and their general suitabilities for human activities are well known, the 

 knowledge of rates of formation and erosion are controversial. More 

 knowledge, especially on agricultural and forested soils, is needed. 



4. Sedimentation: Sedimentation in marine, estuarine and riverine 

 environments is poorly known. A general knowledge of the behaviors of such 

 deposits in other areas has been acquired. Knowledge of suspended sediment 



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